There is the story in Mahabharata : a yaksha asks questions to Yudhisthir
What is the fasting thing ? Answer given is mind
What is biggest amazement : answer given is inspire if seeing people die around us people don’t truly believe they will die too. Sooner or later
In my opinion the most amazing thing is inspite of the truth in front of them , people follow their own ignorance and believe in their stupidity but can’t follow the divine truth given by a rare individual
The story of Yudhisthir is when the 5 pandavas are wandering in the Forrest they get thirsty. They find a lake. First sahadev goes and is told not to drink from the lake without answering the questions from the Yamaha but he does not heed. He drinks and dies. The same happens to nakula, Arjuna and bhima
When finally Yudhisthir goes he listens and has a dialogue with the Yaksha as described above
The real meaning is quite different than described though